Re: [REPORT] kernel BUG at fs/ext4/inode.c:2620 - page_buffers()

[Matthew Wilcox]

On Thu, Feb 17, 2022 at 09:54:30PM -0500, Theodore Ts'o wrote:
> process_vm_writev() uses [un]pin_user_pages_remote() which is the same
> interface uses for RDMA.  But it's not clear this is ever supposed to
> work for memory which is mmap'ed region backed by a file.
> pin_user_pages_remote() appears to assume that it is an anonymous
> region, since the get_user_pages functions in mm/gup.c don't call
> read_page() to read data into any pages that might not be mmaped in.

... it doesn't end up calling handle_mm_fault() in faultin_page()?